Is it the Volume or Water or Size of tank that matters?

This is a discussion on Is it the Volume or Water or Size of tank that matters? within the Beginner Freshwater Aquarium forums, part of the Freshwater Fish and Aquariums category; -->
I'm on the very first stage of considering a larger tank for my fish, but the issue is i have a very specific area ...

I'm on the very first stage of considering a larger tank for my fish, but the issue is i have a very specific area i can keep it in that limits the footprint i can use...

This tank will end up being for two fancy goldfish, a Redtop Oranda and a Black Moor, i have read that length of tank is more important then depth for goldfish, but i'm wondering does volume of tank matter?

Basicly the Largest i can go footprint wise would be 37wide by 13 deep....

Well I would think volume would matter just as much as size when it comes to goldfish. I know the 23 long is just as long as the 45 but I wouldn't but that many fish in the 23 as the 45 due to the volume issue or not as much room so to speak. If that makes sense. I would go with the 45 if it was me.

With the tanks and footprint you have listed, they all have just about the same foot print so the gas exchange is going to be the same. The only thing you can control is the volume. The greater the volume, the more water you have to dilute waste products.

I would go with the largest volume tank for the area. My favorite tank is the 40 breeder 36x18x16 but that is just outside your listed footprint.

The reason i ask is i currently have filters that (are rated to) turn over the my current tank water 24x an hour...so the water is sparkling...even if i go with the 45 i'd be over 15x an hour...

Given Perfect filtration, or atleast filtration to the level i have it...does volume matter, i can't figure out why it would

This is an example of how "filtration" (referring to the filter equipment) is somewhat irrelevant in ascertaining the actual health state of the water.

Filters move water through media. The more this occurs, the clearer the water should be, relative to other things obviously. But clear and clean are not the same thing. A tank can be crystal clear but the water can be highly toxic to any fish. And similarly, the water may be opaque with cloudiness yet be so clean the fish are as healthy as they can be.

Looking at the clean aspect, filters can only go so far. They function biologically with respect to the nitrification cycle. But there is much more to clean water than the ammonia, nitrite and nitrate. There is what I term "crud" that no filter can remove. Dissolved waste, urine, pheromones released by fish, chemicals released by plants... all this crud remains in the water no matter how many or how good the filter equipment. And the more fish or larger fish, the more crud. Goldfish produce a lot of this, which is why they need relatively large tanks.

Crud only gets removed via a water change. So back to your question about volume: the more water in the tank, the less quickly crud will build up. And again, the filter has absolutely nothing to do with this. Now, it does impact via the biological side, because the crud is impacting that too. But the initial crud is still there until you remove the water. The smaller the tank with more fish, the more frequent and larger the water changes must be. This is the water quality aspect of tank size. The physical aspect, namely providing appropriate space for the particular fish to be themselves, is related but distinct.

This is an example of how "filtration" (referring to the filter equipment) is somewhat irrelevant in ascertaining the actual health state of the water.

Filters move water through media. The more this occurs, the clearer the water should be, relative to other things obviously. But clear and clean are not the same thing. A tank can be crystal clear but the water can be highly toxic to any fish. And similarly, the water may be opaque with cloudiness yet be so clean the fish are as healthy as they can be.

Looking at the clean aspect, filters can only go so far. They function biologically with respect to the nitrification cycle. But there is much more to clean water than the ammonia, nitrite and nitrate. There is what I term "crud" that no filter can remove. Dissolved waste, urine, pheromones released by fish, chemicals released by plants... all this crud remains in the water no matter how many or how good the filter equipment. And the more fish or larger fish, the more crud. Goldfish produce a lot of this, which is why they need relatively large tanks.

Crud only gets removed via a water change. So back to your question about volume: the more water in the tank, the less quickly crud will build up. And again, the filter has absolutely nothing to do with this. Now, it does impact via the biological side, because the crud is impacting that too. But the initial crud is still there until you remove the water. The smaller the tank with more fish, the more frequent and larger the water changes must be. This is the water quality aspect of tank size. The physical aspect, namely providing appropriate space for the particular fish to be themselves, is related but distinct.

Byron.

So the Crud factor we can't test for (Unless thats TDS) what would you say would be the difference in the required Water Change schedule on a 45 gallon tank with two fancy goldfish vs a 23 gallon tank with two fancy goldfish to clear the 'crud'...i thought the sponges, polishing pads, carbon and purigen were for cleaning crud? i thought just the bio-media was for the actual nitrofying bacteria

I have TONS of DE available that i can use if that'll help with the crud?

So the Crud factor we can't test for (Unless thats TDS) what would you say would be the difference in the required Water Change schedule on a 45 gallon tank with two fancy goldfish vs a 23 gallon tank with two fancy goldfish to clear the 'crud'

There is no way to test for "crud," it is just there if there is a fish in the tank. I'm not knowledgeable on goldfish other than having learned from other members here that they are big waste producers; I believe someone once referenced 15 gallons to each goldfish of the small varieties. Lupin is well up on these fish, you might want to PM him to check in on this thread.

In my 7 tropical tanks, all of which are fairly heavily planted (live plants have an impact with "crud" too), I change 50-60% every week (at one change) and have for 15 years.

There is no way to test for "crud," it is just there if there is a fish in the tank. I'm not knowledgeable on goldfish other than having learned from other members here that they are big waste producers; I believe someone once referenced 15 gallons to each goldfish of the small varieties. Lupin is well up on these fish, you might want to PM him to check in on this thread.

In my 7 tropical tanks, all of which are fairly heavily planted (live plants have an impact with "crud" too), I change 50-60% every week (at one change) and have for 15 years.

I don't really get how a filter can't pickup and filter out crud...i thought (beyond the limited biological media added) that that was the main purpose of a filter, to filter out crud...granted nothing can pickup 100% but i would think we are advanced enough to atleast get 95-98%

I don't really get how a filter can't pickup and filter out crud...i thought (beyond the limited biological media added) that that was the main purpose of a filter, to filter out crud...granted nothing can pickup 100% but i would think we are advanced enough to atleast get 95-98%

If you looked at my definition of crud you will see it mentions dissolved (i.e., liquified) waste, urine, pheromones and chemicals from plants. This stuff is in the water but not in solid form and can't be filtered out--except by live plants, if you have enough of them and very, very few fish. I read once that 6-7 neon tetra in a heavily-planted 55g tank would be the limit for plants to handle the "crud" produced by those few fish. No filter can.

I can't take credit for "crud," it came from David Boruchowitz who is Editor-in-Chief of Tropical Fish Hobbyist magazine and an experienced aquarist; he coined the term in his 2-part article on the issue of water changes that appeared in the November and December 2009 issues of TFH. He went into the science and math of water changes of 70% weekly and why.